Air-brake apparatus.



H. M. P. MURPHY.

AIR BRAKE APPARATUS.' ABPLIOATION FILED APB.4, 1908.

Patented Feb. 16, 1909.

4 SHEETS-SHEET l [NI 'ENTOR Al/arm'y JTNESSES H. M. P. MURPHY. AIR BRAKEAPPARATUS. APPLIOATION rlLBD APR.4,1908.

l912,714, V Peeenned Feels, 1909.

4 SHEETS-SHEET 2.

INVENTOR H. M. P.l MURPHY. AIR BRAKE APPARATUS.

APPLICATION FILED APE. 4, 1908. 91 2,7 14.

Fw N ...l w@ Mm? .m f m m m U ,L V J @,Hf Fx VJ.\0 N w ...M E m.

H. M. P. MURPHY.

AIR BRAKE APPARATUS.

APPLICATION FILED APE.4,1908.

912,714. Patented Feb. 16, 1959.

4 SHEETS-SHEET 4.

All

y s I. @y f. h 'm /L 7 WW www A;

y 51 mm 11N 7" V/W M/c Zz (1W x' @Ef- D f` ik h m JTNESSES INVENTOR longand short trains,

ortie-r to thus nut-eine n, suon one Apriti e,

To all 'whom it may concern:

Be it known that Heumen M. l?. MUR PHY, e resident oi iittsburg, in thecounty oi Allegheny and VState oi iifennsyivania, have invented certainnewr and, usefuiinprovements in Air-Brake .i'ppsretus`; and l( do herebydeclare the toiletries to' be a full, clear, and exact description orthe invention, such es will enable others slriiied in the art to whichit nppertains to maire and use the SSIIHG. l

My invention relates te improvements in air brake apparatus anni moreperticuierly to tri "ie-valve mechanisms.

ne object of my invention is to provide simple and eiiioientiineans forapply ing, holding and releasing broke cylinder pressure, the said mechasin being so situated and connected 'frita the train pipe,

'auxiliary reservoir, and brake cylinder, that a reduction of pressurein the train pipe will resulty iny anapplication ei the brakes and sothat a rise of trein pipo pressure will, through the medium of the sindvalve mechanism, e'liect the release of the brakes and the recharge ofthe auxiliary' reservoir.

A. further object is te so construct the valve mechanism that it c-liallbe very sensitive toyvariaticns ci t` pipe pressure in order to insureits propo. operation on both orly, in a vulve to which iny inventing aslight to the brake cylet' the in t the re- 's s) throughprompt andaires of the A further object is mechanism of the che vention relates,ineens :amounty of train pipe i incier in service applic duction mede(by om out the't'rain and tinisi positive eppliontien o... train.

*A further object to valve mechanism, ine a large amount et tra.cylinders in :emerge brakes and thus trans out the train.

A further object triple .renting provide ineens in a tripie valve foreffec ne the normal release of the brakes and recher,

e el the auxiliary res- Speef-.cation of .Letters Pente-nt.

i .l l

EPA-[Elin 'l AlPARATUS.

Patented Feb. 16, S1909.

m08. Serial No. 425,193.

[ervoir when the lise of pressure in the train pipe' occurs at amoderate rete,-such as would obtain near the central or rear portion ofa train of average length.

A further object is to provide means for restricting the release of thebrakes and the recharge of the auxiliary reservoir when the rise ofpressure in the train pipe occurs at a rapid raten-such as Would occurat the forward portion of a train,-in order to prevent 'the overchar e'of the auxiliary reservoirs (there locate) and to cause a more rapidflow of air toward the rear portion of the Ctrein, and to retain some'of the pressure in the brake cylinders (on the forward carsyfor a shortperiod after the release is started, in order to make the release moreuniform vthroughout the train and thus prevent the running out of' theslack and thereby prevent the Ujerking, of the cars.

A further object 1s to rovide means for slightly restricting the recarge of the auxiliary reservoirs when the rise 0f pressure in the trainipe is very slow, which may occur near t e rear nd of a very longtrain,- to facilitate the more rapid flow of train pipe iuid to theextreme rear of long trains in order t'o secure a prompt release of thebrakes there located.

A iurtherobjcct .is to so construct a triple valve mechanism that afterthe brakes have been fully applied, the brake cylinder ressure may benuiintained at any desire( degree by the engineer through the Ineduin 0fthe train pipo alone, without in anyway interfering With the sensitive'action of the valves.

l With these ob'viects in View the invention consists in certain novelfeatures of construction and combinations ot lports as hereinaftersetforth and pointed out in the claims.

In the accompanying drawings; .l igures 1, 2, 3, 4, 5, and 6 aresectional views ofthe meehenisrn showing the movable parts in variouspositions; 'l ig. 7 is a plen- View of the seat for the main slidevalve: i; ig. S is o top plan viewI of the main slide valve; l ig. t) ise, top plan view of the secondary or graduating va ve; lf igs. l0, 11,l2, l?) and lel are sectional views of the graduating telve, main slidevalve and cured to the end of an auxiliary reservoir 2 so that thelatter will form a head for one 'end .of the casing, or the latter' may,if desired be providedwith a separate head which may, in turn be securedto any convenient support andprovided with suitable ducts and passages.

A bushing 3 is pressed into the casing 1 andthe lower portion of thisbushing constitutes a seat X tor a main slide valve D which is movablelongitudinally within the bushing, by means of the rod 'n of a piston G,the latter being movable within a chamber or cylinder G1 between one endof the bushing 3 and the opposite head of the casing adjacent to theauxiliary reservoir. l or reasons which will hereinafterl becomeapparent, motion should-not be transmitted to the valve D throughout thefull travel of the piston G andl its rod, but there should be a certainamount of lost motion between said piston rod and the valve. l or thisreason, the' rod l" is provided with two shoulders i12-*L3 for engagingthe valve at respective ends thereof, and these shoulders are so spacedapart that the rod can move a certain distance 1n one direction or theother before engaging the valve.

The rod i? is recessed 1cetween its ends for the reception of asecondary or graduating valve E which has a close fit within said recessso that it will artale of the movements of the rod throng the fulltravel of the latter, and this secondary or graduating valve is pressedtoward its seat on the main valve D, l* y means of a light spring r.

Provision is made at Y for the attachment of the train pipe and thisinlet communicates with a duct S over the bushing 3, the'interior ofwhich latter constitutes the valve chamber itl, and the duct S isconnected with this valve chamtI er through the medium of a duct R, anda portf in the valve seat X. The train pipe duct S also communicateswith a large duct T and at the juncture of these ducts a check valve Cis located andpressed upon its seat ly-a light spring C, and so disposedas to prevent a passage of fluid throu, h the du ct T in thefdirectionof the duct S. T e duct T communicates with ,the valve chamler R1 and,through the forward portion of the latter, with the piston chamber G1.

A duct 4 leads t'o the bra-ive cylinder and this duct communicates witha duct V which latter communicates with a duct U terminating under'aport b in the valve seat X so thatl in certain positions of the valve Das herein- 4positions of the valve,

after explained, brake cylinder air may be` exhausted through a duct din the casing 1, and so that supply fluid may also be admitted to thebrake cylinderf in certain other A duct V14 communicates at one end witha large port a in. the valve lseat X and atthe other end with the duct Vfor the passage of fluid (as controlled by the valves) from the' trainpipe and from the auxiliary reservoir to the brake cylinder, andin theduct V1 a check valve B (held to its seat by alight spring B?) islocated, so as-to revent brake cylinder fluid from entering t e lsaidduct, fromthe duct V.

Iirom an ins ection of Figs. `1 to 6 of the drawings, it wi be seen thatthe ducts R and S are in free communication at all times with the trainpipe, althoughfunder certain conf j ditions, as indicated in i igs.v 4,5 and 6, the' port f is closed by the valve D.

The main slide valve seat', X, contains, in addition to the orts alreadymentioned, ports d and e, therlat-ter being much smaller than theformer, andl both of these ports are connected with the atmosphere bythe duct di, which latter may, if desired, be connected by a suitableipe, with a retaining valve. The valve seat g( is connected hy means ofa duct Ic1 with the chamber Gl at the right of the iston G therein. Agroove gis formed in t e face of valve seat X (as siown in 1| ig. 7) andextends to a side edge thereof, for the purpose' of providing means forbalancing the'graduating valve under certain conditions.

The rod "il` is ada ted to contain, in addition to the spring 1'ereinbefore referred to, v two other springs N and N1. is of moderatestren th and operates to normally hold a rod H3111 the position shown inig. 1. The spring N is comparatively light and presses, at one endagainst the bottom of i its soc-'et in the rod r", while its other endhears against the head'H2 of a valve Ile-H1, which latter is intended toregulate the iow of iiuid through a duct K from ducts W communicatinwith the auxiliary reservoir 2, said duct I terminatin at one e'nd in aface t. The ducts K and may be formed in ti :e head of the auxi'iaryreservoir, which also forms the head of the .chamber G1 as shown in thedrawings, or in a separate head on said' charnler, as before intimated,and

the ducts W piped in any suitable manner 1120 to the auxi'iaryreservoir.

The main valve D contains a cavity m for estal lis` in Jr communicationunder certain conditions zbetween the exhaust ports d and e and the portb, and this cavity performs noother functions atany time except to causethe valve D to be pressed firmly on its seat by the fluid pressurealcove it. The valve D also' has a port 'h which, under c'ertainconditions, communicates witlrtbe port ,130'

also contains a port c Whichy I The spring N1 j operated. That portionof the chamber G1 which is the position 'which the parts will assumewhen the rate of rise of train pipe pressure is moderate, as would bethe case: near the central and rear portions 01"' the averagev freighttrains. It may now be assume that (after the brakes were applied), therelease was made and the rise of train pipe pressure Was moderate. Asthe piston G was forced by this rise of train pipe pressure, toward theright (the train pipe fluid entering the valve chamber R1 and the'pistonchamber G1by the duct R, port f or by duct T orv by both), drawing thevalves D and E With it, 'through' the medium of the rod F,=

said piston iinally arrived at'such position that the restricting vaiveH-H1 Was inserted into the port K, through which latter up to this time,auxiliary reservoir lfluid had free access to the right'hand side ofpiston G.

Continuing its motion, the piston uncovered the groove or passageM1 and,because of the restricted outlet through the duct K, the pressure actingagainst the right hand side of the piston G, instantly rose to `a pointintion of the piston to continue.

termediate that of the train pipe pressure and the auxiliary reservoirpressure, lbut the rise of train pipe pressure is, in this case, as-

sumed to be suiiicient to still cause the mo- This `motion of the pistoncauses the end of the valve H-I-I1 to meet the face t and consequentlyshown in Fig. 1.

Ashown in Fig. 1.

to compress the light spring N, and finally cause the' piston to assumethe position In this osition, the large passage M3 of the duct i forms aby-pass around -the piston G and permits air to` flow into the chamberG1 to the right of the piston so rapidly that, because of therestriction of the port .K by the valve I-I, theV ,''ressures actingagainst lthe -tWo sides ofte piston 'become so nearly equalizedthattheir difference is no longer suflieient to overcome the frictionof' the moving parts and they Will assume the positions It Will beobserved that before the end yof the valve rod H meets the face t, thepassage M1 is uncovered by the piston G and during the subsequentmovement of the latter, the pressure acting against its right hand sideis therefore no longer auxiliary reservoir pressure, but is a pressurehaving a value intermediate the same and train pipe pressure.

auxiliary reservoir 1s receiving a supply The purpose of the spring iv1s to return the piston G across the large passage M3 of duct M afterthe com lete equalization of pressures on the two si es of piston Gandin the auxiliary reservoir, in order to prevent an excessive back flowof air from the auxiliary reservoir to the train pipe when it is desiredto again apply the brakes, but it is equally important not thus tovreturn the piston so as to close the passage i 1, because train pipeleaks, nr conjunction "With a poorly operating train pi e feed valve,lmight then cause the undesire application ofthe brakes.

It will now be readily seen that with the parts in the positions shownin Fig. 1, the of compressed air through the ducts W and the nowrestricted port 'K from that portion of thefchamber G1 to the right ofthe piston G,

and that this portion ofthe chamber is being supplied with compressedair from the train pipe through the passage Ma of duct M, the port K,and passage M3 being so proportioned that the ultimate iioWA of air intothe auxiliary reservoir is fairly rapid. As this Will be the most usualcharging position of the valve, this rate of recharge may be termed thenormal rate. In the position of the mechanismshown in Fig. 1, the mainslide valve D establishes a free communication between the ports b, dand e by means of the cavity m,

Athus permitting a `rapid discharge of brake cylinder air from the duetsV and U to the outlet d1' and thence to the atmosphere. In thisposition, the slide valves valso perform the functionof keeping port fopen andof closing por ts a, and c completely. When the pressures onboth sides of the piston G and in the auxiliary reservoir are completelyequalized, the light spring N will operate to move the piston to theposition shown in Fig. 2 (the main yslide valve of course remaining inthe position shoWnin Fig. 1 because of the lost motion between it andthe rod F), the large by-pass M3 thus being cut oii, but the smallerpassage M1 still being uncovered.

Now let it be assumed that after an application of the brakes, a releaseis made and that the rate of rise of train pipe pressure is Aconsiderably slower than that in the case just explained,that is to say,that the 'rate of rise of pressure is such as would usually obtainbetween the central and rear portions of a very long train. In thiscase, the piston G would be forced toward the right of the chamber GWith only a ,very slight excess of force above that necessary toovercome the friction of the moving parts so that after the valve 'H hasrestrictedtheport K and the piston G has opened the passage M1 and be-'fore the rod of' valve H-H1 has .met the face t, the resultingapproximate equalization of pressures on the respective sidesof thepiston -Will so reduce the force acting on said piston covered thepassage lill,

. ton to approximately assume the positions shown'f'in Fig. l0.

stated,`has just unand the flow ol' air through this passage is capableof building up the pressure 'on the right hand side of the pistrain pipepressure, because' of the Vslight rise of the latter above The piston,as previously that in the auxiliary reservoir and because ol la'. by thevalve H-H."

tlierestriction of port It will now be seen that the rate of feed ofiluid to the auxiliary reservoir, when the parts lare in this positionwhich may be called the compensating recharge and free reis somewhatslower than if .thev larger passage M3 were oen.` Colisequently, theamount of fluid ta ien from the ltrain pipe under the given condition ofa very slow rise of train pipe pressure, is less than would have beentaken had the valve been lable to assume its normal recharge and freereleasev position as shown in Fig. 1. A greater amount of lluid will,therefore, con tinuo to `flow toward the rear portion of the train(beyond the point Where this valve 'mechanism may be located) than would`otherwise be the case and will thus tend to compensate for the largetrain pipe volume and,'as a result,

will provide vfor a more-rapid release of the brakes onthe extreme rearend of the train than has heretofore been accomplished. In this positionof the mechanism, it will be noted lroni an inspection of Figs. 7, 8 andl0, that the cavity m of the valve D establishes a free connectionbetween ports l charge of, brake cylinder air.

and d, thus permitting a free and rapid dis The valves l) and Eperfori'n the saine additional functions in this position as in the`normal recharge and free release l position. lf, alter the auxil -iaryreservoirs at the forward portion of the train have become nearly fullyrecharged and consequently the pressure near the rear o the train,(where the valve mechanism with the parts in thc positions now underconsideration is located) begins to buildup more ray# idly, the valvewill be forced. from this posi* tion, (namely, its compensating rechargeand free release position) to its normal recharge and free releaseposition, as shown in .train Fig. 1, thus permitting 0l' a more rapidreplenishment of the auxiliary reservoir pres-- sure than would bepossible if the 'valve were retained in its compensating recharge andfree release position.v This movement will result from the ,fact thatwhen the risc of pipe pressure is moderately rapid the small groove orpassage M1 is unable to supply train pipe fluid rapidly enough. to theright hand side of piston in order, with the cooperation of the'restricted port l, to

maintain the pressures acting on said piston suiiiciently nearlyequalized to prevent tlicni from overcoming` the lriction ofthe moving-tion of the brakes the release is ma exhaust pori, e, the port d beineclosed.

" ibsequeiitly the tension of .the

moving the 'valve to the posir ,Eiga l. l l be assumed that after anapap parts, d

ica-

by subjecting the mechanism to a very rapid rise of train pipe pressure,such as would obtain at the forwardpcrtion of a train near thelocomotive, ln this case, the motion of the piston to the right will beso rapid and the dillerence between the tra-in pipe pres-v sure and thatin the auxiliary reservoir will be so great that not only Willthekinetic energy of the moving parts tend to carry them to the extremeright, but also the in'- terniediate pressure (built up by thecooperation of the passages Ml and M3 with the restricted port K) actingon the right hand side of the piston G, will be su'iliciently lower thanthat of the train pipe'to still cause sufiicient force to act on thepiston to continue to overcome the friction of 'the moving parts and thepiston will be carried up 'against the end oi its chamber or cylinderG1, moving the 'Valves to the positions shown in Fig. ll. ln thisposition of the mechanism, air will be permitted to flow to theauxiliary reservoir from the chamber G1 through the restricted port K asin the other release ositions; but in this esse, the right hand one ofthe chainber G1 is supplied only through the very rel stricted passageM2. l hns7 although the train pipe pressure is much higher than that inthe auxiliary reservoir, the recharge ci the latter fi ll becomparatively sleuf', thereby inventing for a considerable length of anovercliarge of said reservoir with fluid of a higher pressure than isiuiirnially carried in the ti in rit the time, a incre `d tomird therear ir the nur soso of oi' the brakes ".ion of he .mechricted Ik"se cn(as f fm ol5 the valve 'the port li nh only the small ico there lanisni, i

x may be )l l restric shown ui release el' ifralie cv' itler pressure 'ler retaric'id toa consi' 'equently tend to produce a crm ifi ase of thebrakes throught;

out the zzlwle train, (those. toward the rear ci the i; ain having anunrestricted release as j previously d scribed) and thus the severe"running out el: slack between ille ears which attends the release 'ofordinary forms ci triple valves, will be prevented. 'lhe ad ditonaliterations of the slide valves in this posit'ou are the saine as in theother release wiz., to close ports c and c coni'- f'eep po j open. ilhen the d V against the respective sides o and that in the auxiliaryyres# itirely equalized, the light of the ervoir f ,13o

N'will (as in the case of the normal recharge and free release") .returnthe piston Gr across the by-pass groove M5. 'Hic positions assumed byall the moving parts under these conditions are shown in ti-ig. 2;Wherein it will be noted that a small amount of lost motion still existsbetween theright hand shoulder F2 cf rod F and the slide valve D,

. thus permitting the piston :G to move out beyond the passage M1, whentraveling toward its' service position", before enaging the slide valveD, that is to say; be- ,ore meeting with any appreciable resistance, toitsmotion and thus insuring the sensitive response of the mechanism toslow reductions of train pipe pressure.

It will be readily seen from the foregoing description of the action cfthe mechanism in releasing the brakes, that by providing meanscontrolled by the-motion of the piston G toward its release position,for subjecting the side of said piston opposite to that The gradualreduction of train pipe pressure (such as is usually made in serviceapplications of automatic brakes) v ill causel a siin its compensatingrecharge .55

multaneous reduction of ressure in the valve chamber, R1, and 'in t episton chamber, G1, to the left of the piston G, the air from thesechambers passing out to the train pipe through the port f and ducts Rand S. As the restricted port 1X is of equal or greater capacity thaneven the large by-pass duct M3, practically full auxiliary reservoirpressure u ill act on the right li and side of the piston G, asl theiiov.v of air is new from the auxiliary reservoir to thetrain pipe, andconsequently, regardless of xi hat release position the piston mayoccupy, it u ill be l'orced to the left as the train pipe pressure isreduced. (Under normal conditions, the piston i2 ill be ositiont'or thereasons previously statedv an( the small groove M1 ix ill materially aidin the maintenance of approximately ,full auxiliary reservoir pressureon the right'hand side of the piston-G). rl`he piston G having beenforced to the left, the duct M v. ill be closed and the larger'portion Hof the restricting valve vill be drawn out of the port K, but thesmaller ort'ion lil1 of said restricting valve will be ett 1n sald port,for a pur ose which ii ill be 'hereinafter explained: A ter taking upthe -lost motion between the rod F and valve D,

the rod F will cause said valve to move *with it to the left and becauseol pushing (instead of pulling) of this valve by the rod F, thegraduating valve E vill be in its extreme left hand position withrespect to the main slide valve D and will therefore connect portsshovvn in Fig. 3, that auxiliary reservoir air entering the chamber G1behind the piston through the 4partially restricted port l, is free topass through the duct'c1, ports c and h, cavity p, ports k and b andducts U and Y to the brake cylinder. The object ofpartially restrictingthe port K at this time is to permit the ports and ducts conveying therluid from the rear of the piston to the brake cylinder to bring about asuliicicntly rapid reduction of pressure behind the piston to cause itto become approximately balanced and thus prevent its further motion tothe left. lThe registration oi' the small port vith the port a permitsof aslight tio-zr' ot train pipe iiuid to the brake cylinders in orderto assist in transmitting the reduction of train pipe pressurethroughout the train and to slightly augment the pressure obtained vinthe cylinders. It v; ill be noted that the air thus admitted through theport Z to thc brake cylinders must enter the latter by pass- "ing thecheck valve/B, which latter at all times prevents a back iloiv of airthrough the duct o.

train pipe if the lat-ter be made through the 'port alone; consequentlyas soon as the engineer stops the reduction of train pipe pressure byineans'of his brake valve, the pressure behind the piston G i: ill fallbelov; that This position oi the valve may be. vtermed' its Luck serviceosi'tion" and is )n n r v n l shoun in Fig. 3. ll'ie relative sizesottnc in front of it and said piston v, ill move to the A right. 'lhoslight diil'erence of pressures required to cause this motion is merelySullicient to overcome the friction ot the piston and the graduatingvalve, so that v lient he piston has moved until the left h and shoulderF3 engages the main slide valve, its further niotion v ill be stopped bythis means becausejit requires considerably more toire to move the mainvalve than is necessary to move the pist n and graduating valve alone.By this means therefore, the mechanism is caused to assume a "lapposition, the parts being lo- `pipe pressure isinzide et n 'fairly slow`the port Z has passed over the port e',

' ing Valve E will be caused to assume u.

sieg/ie cated With reference to euch other and to the seat as shov. ninFig. 12. lt n ill be observed vthat the graduating vslvevE has newclosed the 'port L and disconnected and closed the ports h and lc. 'lhisposition of the niechen- )rnuy--be termed the fquiclt servicelepposition. Ifvnow, e. further trein pipe reductionismade by thelengineer, the piston -tigain' -move to the left und first cause."lo'andh to be oonnectedby Ineens of lie'ri'grduating valve and thenuncover port l ,-ljfhus permltting a further flow of auxil- -`laryreservoir air and ol tram pipe en' to the brake. cylinder. rl'lie objectin connecting the auxiliary reservoir and brake cylinder portsbefore theport l is opened, is ilo prevent very slight train pipe reductions,(such es occur from leakage) from causing4 the venting of train pipefluid to the broke cylinder, as such veniing n ould only ainplil'y theobjectionable results obtained from such un-- desired reductions ol'trein pipo pressure.

, rllie quick` serviceJ position of the ineclii eiiisrn (i. e.,-thatabove described und shown in. Big. 3) is the position which will hesunied when the service reduction oi" trein enger is the cese on mostfreivht und long ptrains. tion is mede on short trains und consi quentlyfairly rapid, the inecln 'sin in: suine a position (as shonn in lig. i3)to .l left of its quick service position, :ind which.. may be termed thefull service nesiiion. .ln this position oi' the inechnnisifn, iii 1,and 7i and bV and le .are freely connect-1,

trein sequeiitly Will no longer permit u llov.' oi

pipe fluid to the brake cylinders, i it (under the conditions sssuined)i: not .only unnecessary but un when ille auxiliary reservoirbfi-.cornev depleted to e `point sli that ol the trein pipe pressure, u

l A idf; i position as slt-.own in liig. l,wliieli posiiion may beterined Hfull service lap position.

lf the train pipe pressure be reduced, nl; the service rate, to such slow desfiee limi the pressure in the brake cylinder nus become equal-tothat in the auxil. f' resirtoir, n further reduction oi train pipe prwill.' obviously cause the nston G to inove the slide valves to the letol' their servico posii .tionsvfor' (because of the equalization oipressures in the brake' cylinder und auxiliary reservoir) the pressurein theuuziiliniy reservoir cannot drop any lower, as e result oi thisnio- .tion of the parte to the left. lonsequently, the vmotion of theparte will continue until the port f is closed by the valve D," snc'thus all further flow ot air from the vulve cliunilier R1 to the ftrziinpipe is prevonled. 'i lio valves will .now assume the positions illus--tinted inFig. 4, wherein it is shown that the lio vf l l l l moved ferenough to open or uncover the ducts or grooves L1 L3. 1 .During theInovenient of the vulve D to this position, it is clear from thespucesexisting between the ports, that first, the ports c und b x'veiecoinpletely closed and then the port a was slightly opened; after whichthe portf was closed.. During this saine movement 'und :it :ill times,the chock vulve B prevents u flow of iluid li'oin the brake cylinderthrough port a to the slide vulve chamber.` 'lhe object of closing theports b and c before uncovering the por*U d is to prevent nny flow o'nir freni the train pipe (when the pressure is enlise quently rnisrd ,insind pipe) through port u, ducts "71 und U und ports l), h and c andcavity p und duct e* to the auxiliary re voir, us this would obviouslyinteriore ,th Lhe proper rele-.n of the brakes. lhe object in slightlyopening port u before clesin; ieri;

,f is to provide ineenswhereby, in eniergeney hen, however, itheservie-'e reducapplications und in euse the brake cylinder pressurebecomes deil'iletcd by lool-tuffo ,after oquulizittion, the lourpressure in the brake eylindor een muso flow ol air from the pistonchamber G1 :it the left oi' tue piston, pest the check vulve B, und thusoiiuse the auxilini'y reservoir pressure to force the piston to cxlwineleft hund positieu,--siinultuneously openingport u. n ide und permitting:sir to flow ironi the euxilinrv reservoir through the grooves L1, L2,duct l und port t to the lirnlie cylinder. y

"vi lieu fthe parte oiz the mechanism Auisuine l i equalization l:position or :my other po sillon Where the pislon is lfb dicuied in Fig.l und the inn-in vulve hes un overed the port a; itl", nltenieducing the'train pipe pressi ulliciently to muse the inoelninisinto assume such eposition any pressure equal to -oi' .less than this reduced inessure lieinuintniiud in the trein pipe 'through the .incdiuni ol u properlyz-idiusted reducing vulve under the control of .the engineer, the brakecy. nder pressure cannot drop l below the inu'lntaiintd pressure in thotrain pipe, :is aires, under the conditions stated,

perfectly 'ree to flow 'roin the trein pipe to the brake cylinder byopening the check valves C und Bund llowiinz through the ducts S und Tand port u und ducts V1, V and 4. 'l hns it will be seen 'li'nit themechanism. provides usiniple und el'lieieni. inea-ns furthe maintenanceo'llirnke ci'fliml-oipressure in spite ol leakage, und yet: in no vvn-yinteriores sith the proper :n."lion of the nieclninis'n hen zi. releaseis desired, ns uni'ler the condifl, tions stiitmh there is no wey lorhouir to enl e position in.

"not embody a maintenance feature.

ter the auxiliary reservoir and consequently the release may be effectedwith as much ease as in the case of other triple valves which do It isalso evident that this feature, as embodied in my improved mechanism isentirely automatic (as long as the train pipe pressure is maintained)and that it in no Way interferes With the satisfactory operation of thevalve when operated on trains having the ordinary forms of triplevalves, but will o )crate in perfeet unison with them under ailconditions.

Consider, new that the mechanism is in one of its release positions andthat the train pipe pressure is suddenly reduced in order to cause 'anemergency application of thel brakes. This will, of course, eilect arapid motion of the piston and slide valve to the left, causing them topass over their service positions, as the reduction of pressure in thetrain pipe is so rapid that the pressure behind the piston cannot fallas rapidly through the service ports and consequently the parts moverapidly to their extreme left hand positions, as indicated inA Fig. 5.The port f is new closed and the port a is Wide4 open. The

` ports b, c and-e are also closed and the cavity m of valve D isresting over port d and thus exposing alarge portion of the area of theface of the valve to atmospheric pressure in orderto permit the leupressure above it to hold it to its seat, notwithstanding anytendencythat the higher pressure existing in` the small port c may haveto lift it from its seat. In this positionof the main slide valve, theport 7L therein. registers with the small groove g (see Fig. 7) and thusinsures the complete balancing of the graduating valve E, the cavity ofwhich connects with the port h at this time, by admitting the same)ressure beneath it that exists above it. As the valve moves beyondits-l service positions toward that vshown in Fig. 5, although allfurther flow of air from in front of the piston to the train pipe is-stopped the instant that v,the

. port f is closed, still, as -the lport a is opened before port f isclosed, a very rapid reduction of pressure new occurs from in front ofthe piston through the port a, and its connecting ducts to the brakecylinder. In tact, the opening of tl 1e port a not only insures the fulland rapid motion oi" the piston and valves to their extreme left handpositions, but also provides means for rapidly-venting a large amount oftrain pipe fluid to the brake cylinder (train pipe iiuid passing bycheck valve Cand through ducts S and T and port a to the brake cylinder)in order to assist in trans. mitting the emergency reduction of trainpipe pressure-throughout the train and to augment the cylinder pressure.

From an ins ection of Fig. 5, it Will be observed that t e' movementofthe piston G is limited by the end of the bushing 3 and that anyover-travel of the main slide valve D is prevented by the abutment a1 inthe nut closing the left hand end of the casing. In

. Fig. 5, it is also shown that the portion H1 of the restricting valyehas been removed by the piston from theport K and consequently a freeflow of air from the auxiliary reservoir t.

is permitted through the orts W and K, around the piston G throug 1 thegrooves L1, L2, and through the ductQ and port a to the brake cylinder.rihis ioW of auxiliary reservoir air isl sufficiently restricted to perymit a large amount of train pipe fluid toenter the cylinder; it .beingevident ,as previously pointed out that a free path is provided in theemergency position (as there illustrated) for the passage of train pipeiiuid to the cylinder. chamber finally tends to become greater than thatin the train pipe, the check valve C is closed by its spring and a backflow of air to the train ipe 1s thus prevented as the port f is also cosed as previously pointed out. When the pressures inthe auxiliaryreservoir and brake cylinder (said pressures now acting on theyrespective, sides of piston G) become approximately` equalized, themoving parts Wil assume the positions shown in Fig. 6,-Which positionmay be termed emergency lap position. The main valve D is lstill in itsemergency osition, but the piston G and graduating va ve E have beenmoved slightly to the right, thus cutting oil the grooves L1 and L2.This motion' of theI piston is caused by the spring N1 through themedium of the rod H3 as clearly indicatedl in Fig. 6. The object ofbalancing the graduating valve as previously described is nowapparent,-viz.to insure the least possible resistance to the backwardmotion of the piston G, in order to make its return by the s ring N1positive under all conditions, and t us insure the easy and sensitiverelease of the brakes, When the train pipe pressure is subsequentlybuilt up, by cutting oil all communication (through the grooves L1 andL2) between the auxiliary reservoir and the train pipe in this positionof the piston.

)When it is desired to release the brakes at any time when the port f isclosed 'by the main slide valve I), it is evident that the train pipefluid may pass Jfreely by the check K valve Cinto the chambers R1 and G1and thus act on the iston G and force it at once towardits releasepositions.

Having fully described my invention what I claim as new and desireto'secure by Letters-Patent, is

1. 'I'he combination in a triple valve mechanism, of a valveforcontrolling the application and release of the brakes, a pistonvconnected with said valve, a chamber in which said pistonis contained,means for normally admitting auxiliar reservoir `fluid into said chamberat one si e ofthe piston, means for permitting a flow of train Dinefluid into the Wheny the pressure in the slide valve so l.

loe

' piston, means for permitting a ilew oi. luid from said controllingspace to the train pipe under certain conditions, and means forpreventing the 4lloW of fluid from said controlling space to the trainpipe under other conditions.

y 2. The combination in a triple valve nicchanism, of a valve forcontrolling the application and'release ot the brakes, a pistonconnected with said valve, a chamber in which said piston is containedand constituting at one side of the latter a controlling space,

means for normally admitting auxiliary reservoir lluid into said chamberat the other side of the piston, means providing two paths for trainpipe luid 'into saidcontrolling space and means for preventing at alltimes the passage of Huid from said controlling' space to the train pipethrough one oi' said paths.

3. The combination in a triple valve mechanism, of a valve forcontrolling the application and release of the brakes, a pistonconnected With said valve, a chamber in which said piston is containedand constituting at one side of the latter a contrelling space', meansfor'normally admitting :nixiliary resevoir fluid into said chamber atthe other side of the piston, means providing two paths for train pipefluid linto said controlling space and means for preventing at all timestie passage of iluid from said controlling space to the train supplythrough one oi said paths, and means lor opening` and closing the otherof said paths between train pipe supply and said controlling space.

4l.l The combination in a triple valve mechanism, ol' a valve forcontrolling the application andrelease of the brakes, a piston connectedwith said valve, a chamberin which said piston is contained andconstituting at one side of thelatter a controlling space, means fornormally admitting auxiliary reservoir [luid into said chamber at theother.

side of the piston, means providing two paths for train pipe iuid intosaid controlling space and means for pieventing at alltimes the passageol' lluid from said controlling space to the train pipe through one ofsaid paths, and means controlled by the movements ol'v said valvcloropening and closing the other of said paths.

5. The combination in a triple valve mech- Ianisim of a valve forcontrolling the applicaggg,

to close the other path when said valve has passed its serviceJ positionin its movement toward its emergency position.

6. T he combination in a triple valve meclip anism, of a valve forcontrolling the application and release of the brakes, a pistonconnected With said valve, a chamber in which said piston is containedand constituting at one side ofthe latter, a controlling space, meansfor normally admitting auxiliary reservoir fluid into said chamber atthe other side of the piston, means controlled by the movement of the.piston for permitting a l flow of fluid from said controlling space tothe train pipe under certain conditions, and means controlled by themovement oi the piston for preventing the flow of iluid from saidcontrolling space to the train under other conditions.

7. In a triple valve mechanism, the combination with a casing, a pistontherein, the space at one side of said piston constituting a controllingspace, means for nori'nally admitting auxiliary reservoir lluid at 'theother' side of said piston, of valve devices for con-- trolling theapplication and release ci the brakes, located in said controlling spaceand connected with said piston, means for pei'- mitting a llow of trainpipe iluid into said controlling space, means for permitting a lloW oilluid from said controlling space to the train pipe under certainconditions, and means for prevent-ing flow of -lluidlroin saidcontrolling space to the train pipe under other conditions.

8. In a triple valve mechanism, the combination with a casing, a pistontherein, the space at one side ol said piston constituting a controllingspace, means for normally admitting auxiliary reservoir fluid at theother side oi' said piston, of valve devices for con-` .trolling tlie aplication and release of the brakes, locate in sziid controlling spaceand connected with said iston, means i'or permittino a flow oi' trainpipe lluid'into said controlling space, means for permitting a flow olfluid from said controlling space to the train pipe under certainconditions, and

means for preventing flow oHluid from saidA controlling space to thetrainpipe under other conditions, 'said casing having means ol'communication with the brake cylinders,

and said valve devices provided with means operative under certainconditions te permit a flow of fluid 'from said controlling space to thebrake cylinders.

9. ln a triple valve ineclninism, the combination with a casing, apiston therein, the space at one side of said piston constituting acontrolling space, means for iiormallj,T admitting auxiliary reservoirlluid at the other side ol` said piston, of valve devices forcontrolling the application and release of the brakes, located in saidcontrolling connected with said piston, means for pei'- space and meansfor exhausting air from vlf@ ' other conditions,

I and Inova-iii mitting a flow of train pipe fluid into said controllingspace, means for permitting a lioW of fluid :from said controlling spaceto the train pipe under certain conditions,- and means for preventingiloW of fluid fromzsaid controlling space to the train pipe ufncler saidcasing having means of communication With the brake cylinders, and meansin said valve devices operative in one position to permit the lo'vv o1"a small amount of fluid to the brake cylinders, and in another positionacting to cause a large amount of fluid to lloW to the brake cylinders.

l0. in a triple valve mechanism, the coinbination With a casing, apiston therein, the space at one side of the piston constituting acontrolling space, means for normally admitting auxiliaryreservoir fluidto the other side of the piston, und ducts Afor brake cylinder fluid, ela main slide valve in said controlling space, a lost-motion connectionbetween said valve and the piston, a graduating valve mounted en themain slide valve by the piston a limited distance independently ol" themovements of the main valve, said main valve and its seat having meansfor exhausting air from -a brake cylinder duct, d uct for conveyingauxiliary reservoir lluid to said main valve, both of said valves havingpassages cooperating' to direct such auxiliary reservoir liuid to theliral-:e cylinder duct, means for periuittil'ig a flow of train pipeliuid into said control-ling space, means for permitting a flow oi fluidfrom, said space to the train pipe under certain conditions, and meansfor preventingr a llow of fluid from. said controlling space to thetrain pipe under other conditions.

l1. ln a triple valve mechanism, the coul bination with a casing, apiston therein, the space at one side ol the piston constituting acontrolling space, means lor normally adinit ting auxiliary reservoirfluid to the other side ol' the piston` and ducts for liralfge ofimderlluid, ci' a main slide vulve in .said centrolling space, a lost-nuitionconnection l e tween said valve and the piston, a gradu ating valvemounted on the main slide valve and movable by the piston a limiteddistance independently oi' the 'movements of the 'main valve, said mainvalve and its seat having a brake cylim der duct, a duct `lor conveyingauxiliary reservoir fluid to said. vmain valve, both ol' said valveshaving passages cooperating to direct such auxiliary reservoir lluid tothe brake cylinder duct, means l'or permitting a flow of train pipefluid into said controlling space, means vfor permitting a liow of iluidfrom said space to the train pipe under certain conditions, and meansfor preventing a lloiv of fluid from said controlling` space to thetrain pi e under other conditions, and. means control ed by the valvesfor allording a l'ree l I l l l l l l l l l l l l i l l l l 1 Il i.

l l l l l l l clavie lloiv ci train pipe fluid to the uralre cylindersin emergency applica/ions and a restricted iiov; ci' train pipe fluidthe brake cylinders in service applications the brake.

ln a triple valve mechanism, the com hination With a casing, e pistontherein, the space et one side el said piston constituting a controllingspace, and means fornormally admitting auxiliary iiuid at the other sideof the piston, oi valve devices connected With said piston, forcontrolling the application and release or" the brakes, meansiorpermitting a iicw of train pipe iluid into seid controlling space,ineens for permitting a llovf of liuid from saifA controlling space tothe train pipe under cert-ein eenditions, means 'for foreventing a lievioit ilnid frein said controlling space to the ti Qi p ve under otherconditions, and means cpe ci iluid from the bra-lie cylinders trollingspace at all times.

13,. ,in triple valve mechanism., the com` bination with. a casing, apiston therein, the space at one side of said piston constituting acontrolling` space and means for norinz'iily admitting auxiliaryreservoir lluid. at the other ide of the piston, of valve deviceseennected with said piston, for controlling the application and releaseel' the brakes, means for permitting a flow of train pipe fluid intocontrolling space, means for permitting a loiv 'oi' iluid. from saidcontrolling space to the train pipe under certain conditionsmeans forpreventing a ilovv of lluid from said contrcliii'ig space te the trainpipe under other Ike cylinder duct, a duct ting t. l

to/,the cogi- 'aire cylinder duct a p conimunic ai i d lia-ving wing'from the brake Y ccntivilling space in tn,

` lianisin, the comi a piston therein, said piston ccnstitutmeans foradmitting ud at the other side oi' ,l ire cylinder duct, valve dtv-leesconnected with and controlled by the movements oi said piston, saidvalve devices havinn ports and passages cooperating te close directcomnninication between the auxu servoir and the lnake cylinders wheny[Finder and. auxiliary reservoir yipproximately equal and as ssure insaid controlling space ely equal to the auxiliary rese-f'- a triplevalve nicciianis i., the ccmliination with casing, of a piston therein,tile space as one side cfsaid piston consi ,ut-

con'rolling space, means for adn'iitting iluid at the other side of iniauxiliary niscrvoir ng to prevent a lieviv ting at all time-sto seid.piston, velvedevices connecteil with seid piston 'lor eontrolhng thenpplicetion find release of the brzil'ies, tivo paths tor vtrein fluidto. seid eontrollincs ece e check vnlve in one of seid petits, ineenseoi'peroting With'seid valve devices to close the other of scid treinpipe huid paths and to 'fully open communication between the nufiiliziryreservoir and the brake cylinder, and spring-:ictu- -ziteel Ineensoperating to actuele said valve tween sind controlling spore :ind thebreite 'ovlinrler connections, sind estr-.h-lishii'ig; coniniunicstionbetween the uuxil .iry reservoir and the broke cylinder connections,rind n springr tending'to eil'eet he closing ol' conn inunirntionbetween the lirrilre ij-ylin ncctions :ind the inixiiiziry reservoir.

17. in e triple volvo inoclizinisin, the corri-.-

, bimition with ai casing, oi' zi piston therein.

ineens for subjecting one side. ol" seid piston to auxiliary reservoirpressure, the spare nl. the other side ol' seid piston constituting u..controlling Splice, ineens 'lor admitting trein pipe fluid to sindcontrolling,l space, braille I cylinder connections, ducts controlled bythe movement of sziid piston 'for idinitting' auxiliery reservoir lluidto seid controllin,r sparco, valve devices connected with said piston,seid valve devices provided with ineens for openings,l conununicntionbetween sriid controlling spfice :ind the brake cylinder conne ltionsind estublishing coniniuniczition hotiveen the auxiliary reservoir :indbrrr-lie cylinder connections, u. check valve in said brake cylinderconnections permittingf n flow ot lluid through the hitter lroni the controlling; eprice, und e spring tending to opernte the piston to closecon'imuniczition be tween the bra-ke cylinder connections :ind the:iuiliery reservoir.

18. ,ln n. triple vulve niechzinisin, the rouibinetion with ii casing.ol e. piston therein. the sparco et one side. ot' seid piston..@oiistituingA n controlling space, ineens lor sul@ ,ciingg the otherside oi seid piston to auxiliary reservoir i'iressure,- brake cylinderconnections, ineens 'for 'establishing conin'iuniciition bew tween thetrein. pipe end seid controlling space sind ineens controlled by seidpiston for establishing wunniunioetion between seid controlling spare:ind the broke cylinder ronnections.

' 19. in e triple vulve nieclninisni, the conn .vulve devices controlledRifle binetion with ii easing, of e piston therein, the spese et oneside of seid piston consti toting e controlling space, means forsubjecting the other side oi seid piston to auxiliary reservoirpressure, brake cylinder connections, ineens permitting e llow of train-pipe fluid nt :ill times to the controlling space, ineens. controlledhy the piston for opening communication between the controlling spaceend the brake cylinders, nien-ns constituting another path between saidcontrolling space end the train pipe, sind ineens controlled bythepistonfor closing seid lestunentioned path after communicetion between thecontrolling space and the brake cylinders has been opened.

2t). ln e triple 'vnlve inechenism, theconibinetion with a casing, episton therein, und vulve devices controlled by seid piston to controlthe application and ieleese of the bruises, of ineens for subjecting onesidev of sind piston to trein pipe pressure, ineens for outing;euxilinry pressure to the other side ol: the piston, ineens controlledby the inert-ments of the piston to control the ed misi-ion elauxiliaryreservoir luid to the chinnber containing the piston, find e duct i con:rolled hy seid Valve devices lor conveyzuig lluid troni the side of thepiston :it which .iuxilinry reservoir fluid enters, to the brokeVlinders.

2 l. ln o. triple vulve inechiinisiii, the coni- `biimiion with ncasing, n. piston therein, and vulve devices roi'itrollcd by seid pistonto control the application and relenso oil the breites, ol ineens 'forsubjecting one side *of seid piston to train pipe pressure, ineens ofconnnunicetion for the passage of auxiliary reservoir 'lluid to theother side ol seid piston, sind nicnns controlled by seid piston forrestrict-ing sziid ineens of communication of auxiliair-y reservoirfluid, sind o. duct controlled by seid valve devices for conveying iluidfrom theI side of the piston at which auxiliary reservoir l'luid enters,to the brake cylinder.

212. in n triple vulve inechnnisni, the coni` binntion with i casing, npiston therein, :ind Ynlro devices controlled by siii-d piston i'orcontrolling` the application und relcnso of the` hrnices, oi' ineens lorsubjecting one side of smid piston lo trein pipe pressure, n duct ioradmitting; auxiliary reservoir Ylluid to the other side ol seid piston,sind i valve dcvif-e controlli-ul hy said piston for varying the de-,rtree o't' vllow of auxiliary reservoir l'luid through said duct, andai duct controlled by scid vulve devices-for conveying lluid l'rein theside ol the piston at which auxiliary reservoir fluid enters, to thebrake cylinders.

22%. ln fi triple valve niecl'ninisni, the combination. with :i casing,ii iiston therein, und liy seid piston for controllingr the :ipplicslionend release of the breites, ot nien-ns for .subjecting one side of siesaid rod having a diameter appreciahly less than that of saidrlucnwlierehy .duct is restricted, anda duct controlled by said XValvedevices for conveying fluid from the sideof the piston at Whichauxiliary reseryoir fluid enters, to the brake cylinders.I

24. ln a triple' valve nieclian'sin, the com:

bination With a oasinna piston therein, and Valve devices controled bysaid piston to control the application and. re oi' th brakes, lof meansfor subjecting side said piston to train pipe pressure, a duct ic:conducting auxiliary reservoir fluid te "lie other side of said piston,and a rod carried the piston and adapted to entersaid duel' l"restricting the saine, said rod hr rality of portions di'ering in sizeother, the greatest size of said rod 1being appreciablyless than thesize said duct, and a duct controlled' hy said valve devices forconveying fluid' from the side of the piston at Which auxiliaryreservoir uid enters, to the brake cylinders.

25. In a triple Valve niecliauisnn the com bination with a casin'gf, apiston and valveA devices controlled by said piston for controlling theapplication and release ci brakes, of means for subjecting one side ofsaid piston to train pipe pressure, means .i r normally introducingauxiliary reservoir :fluid at the other side of the piston, and meansfor subjecting the oT at which auxiliary reserver Inally introduced, toy es.. diate that, of trein pipe presen e uns iaiy reservoir pressure.

25. ln a triple Valve meehanisin bination With a casing, nist' i.. valvedevices controlled hy sai controlling the application and r brakes, ofmeans for suhjecti said piston to pine press .A normally introducing au:'lia u l iluid at the other side oi the pieton, and means controlled bythe piston for subjecting the side of the piston at which auxiliary reservoir fluid is normally introduced, to s. pressure intermediate that oftrain pipepressu're and auxiliary reservoir pressure.

27. ln a triple Valve mechanism, binaticn with a casing, a pistontherein, and valve devices controlled ley said piston for controllingthe application and release oi the brakes, of means for subjecting eneside of said piston to train pipe pressure, means for normallyintroducin auxiliary reservoir fluid at the other site oi' said piston,and means for subjecting said piston et 'the side thereof at whichauxiliary raser; oir fluid is normally intro'ducei'l after tile pistvalve devices have reached the comn ion! elle t in 'DiS :Lilli lassures, und

ne erases, to a pressure inter t ,line jressure and auixil seri/oirpressure. lic a triple valve mechanism, the eem nineties with a casing,a piston therein, Aand valve devices controlled by said piston, saidiston and rallye devices movable to a plul i release positions, of meansfor suiijecting one side of said piston to'train pipe pressure duringits movement toward its release positions, means for subjecting side ofsaid piston to auxiliary ereesure -unlil the of said has been reached,lor subjecting 1 this last menol the piston to a pressure interausiharyreservoir and'train. pipe means for augmenting the el sara i l' pressureduring ton toward its sec release position, ln a triple valve mechanism,the coini with a casino?, a piston therein and devices controlled bysaid piston for 'rollig the application and release of the brauen .meansfor subjecting one side of said l first Urelease l)iston to train pipepressure, means for nor inV *reducing auxiliary reservoir fluid at theotner side of the piston, means controlled by 'the piston for subjectingthe side of the piston which auxiliary reservoir fluid is ii oduced, toa pressure intermediat that oi train pipe pressure and auriliai"Treservoir nressure and means coperatin with said last-mentioned meansfor chargreservoir a slightly ref, a piston. therein' and 'led by saidpiston for the application and release oi the ineens for subjecting oneside of on to train pipe pressure, means for .lntreducing auxiliaryreservoir fluid side oi the piston, means oonlie piston subjecting theside ,u clon at which auxiliary reservoir normally introduced, to apressure inteunediate that olj train pipe pressure and au reservoirpressure, and means coperanng ri/ith said last-rnentioned means forcharging' the auxiliary reservoir at a slightly ,flote-d rate, andsimultaneously@ erat i a triple valve mechanism, the cornenia i n acasing, a piston therein, and

5 y .'B T D ere until the nrst release2 posi rue-ans controlled by saidyalvedevices to 'ircely open the brake cylinder exhaust.

c va mechanism, the coirtion ofthe piston has been reached, means forsubjecting this last mentioned side of the pis-- 10 the normal rate.

' 32. In a triple valve mechanism, thecombination'with a casing, apiston therein, and valve devices controlled by said piston, saidpistonv and valve devices being movable to a plurality of frcleasepositions, of means for subjectin one side oi said piston to train piperessure uring its movement toward its rej ease positions, means forsub'ecting the l'other 'sideof said piston to auxiiiary reservoirressure until the first release posi- ;tion as been reached, means forsubjecting this last mentioned side oi the piston to a pressureviniterniediate auxiliary reservoir and train pipe pressures, means foraugmenting the degree of intermediate pressure dur-.

ing the movement oi' the piston toward its second "-release position,means coperating with said last-mentioned means for charging theauxiliary -reservoir at the normal rate, and means formateriallyrestricting the rate of charging of the auxiliary reservoirwhen thepiston moves beyond its second release position.

33. In a triple valve mechanism, the com- 36 bination with a casing, apiston therein, Vand valve devices controlled by said piston, sa-idpiston and valve devices being movable to a plurality of releaseositions, of means for subjecting one side oi' said piston to train 40pipe. pressure duringts movement toward its release positions, means forsubjecting theother side oi'said iston to auxiliary reservoir pressureuntil t 1e first release position has been reached, means for subjecting45.' this last mentioned side of the piston 'to a pressure intermediateauxiliary reservoir and train pipe pressures, means for augmenting thedegree of intermediate pressure during the movement of thc piston towardits sec- 50 ond release position, means cooperating with saidlast-mentioned means for charging the auxiliary reservoir at the normalrate, and means for materiali Trestricting the rate of charging of theauxiliary reservoir when the piston moves beyond its second releaseposition, and means torrestricting the brake cylinder exhaust. when thepiston moves beyond its second release position.

34. in a triple valve mechanism, the combination with a casing, a pistontherein, and valve devices controlled by said iston, said piston yandvalve devices movab e to a plurality of release positions, oi means forsubjecting one side oi said piston to train pipe pressure during itsmovement toward vits release posi-tions, means .for subjecting the otherside oi said iston to auxiliary reservoir pressure until t ie -firstrelease7 position of said iston-has been reached, means foi" thensubjecting this last mentioned side oi the` piston to a pressureintermediate aux iliary reservoir and train pipe pressures, means foraugmenting the degree of said intermediate pressure during the movementof said piston toward its second release position, and simultaneouslyoperatingmeans controlled bysaid valve devices to freely open the brakecylinder exhaust. V

35. ln a triple valve mechanism, the combination with a casing, a pistontherein, and A valve devices controlled by said piston, said piston andvalve devices boing movable to a lurality oi release positions, of meansor subjecting .one side of said piston to train pipe pressure during itsmovement toward its release Jositions, means foisubjecting the othersido of said piston to auxiliary reservoir pressure until the iirstreleaseH position or' the piston has been reached, means ior thensubjecting this last montioncd side of the piston to a pressureintermediate auxiliary reservoir and train pi e pressures, ineans foraugmen ing the ciegree oil said intermediate pressure during themovement of said piston toward its socond release position, meanscooperating withsaid last-mentioned means for charging theauxiliaryzreservoir at the normal rate, and simultaneously-o eatingmeans controlled by said valve evices to freely open the brake cylinderexhaust.

36. In a triple valve mechanism, the combination with a casing, a istontherein, and valve devices controlled )y said piston for controlling theapplication and release of the brakes of means for subjecting one sideof said piston to train pipe pressure, a duct for normally introducingauxiliary reservoir iiuid at the other side ol the iston, and means forsubjecting the side o' the piston at which auxiliary reservoir iluidisnOrmally introduced, to a pressure intermediate that of train pipepressure and auxiliary reservoir pressure, said last-mentioned meanscomprising a valve device controlled by the -1i5 movements of the pistonto restrict the auxiliary reservoir iluid duct, and a passage controlledby said piston to permit train pipe iluidfto pass to the sido oi thepiston at which auxiliary roservir iluid is normally admitted.

37. ln a triple valve mechanism, the combination with a casing, a pistontherein, and valve devices controlled by said piston `for controllingthe application and release of the brakes, of moans Tor subjecting oneside oi said piston to train pipe pressure, a duct for normallyintroducing auxiliary reservoir fluid at the other side of the piston,means for subjecting the side 'of said piston at

